IMPORTANT - READ BEFORE USING:
In the planner there is one advanced heat dispenser. You need to replace that with a near-depleted uranium cell (or an isotope cell which will not be recharged) to generate 1 heat/tick. If you don't, the breeder will cool down slowly.
Also notice there is no external heating or cooling.
This is a CASUC breeder, designed to run at OVER NINE THOUSAND heat (HAYO!), which can easily be obtained by adding 5 lava buckets in place of one of the plates. No wait time is required between buckets as the hull is the only component which stores heat. Before adding any lava, ensure the reactor is on and ice is being supplied. This heat level is not high enough to damage entities.
The reactor will use exactly one piece of ice per second. No external timer is needed to maintain this rate, as it can only use one piece per stack per reactor tick.
The one downside of this design is that three of the depleted cells are adjacent to *two* uranium cells (this was needed to maintain heat). These cells must be replaced four times per cycle or the reactor will cool down, while the other cells must only be replaced twice per cycle.
This variant adds two extra isotope cells, and nine more to keep the heat balanced instead (near-depleted cells can also be used for this), but allows all the cells to charge.